U.S. patent number 10,196,926 [Application Number 14/683,824] was granted by the patent office on 2019-02-05 for lubricating a rotating component during forward and/or reverse rotation.
This patent grant is currently assigned to United Technologies Corporation. The grantee listed for this patent is United Technologies Corporation. Invention is credited to Denman H. James, Reade W. James, David A. Ketchum, William G. Sheridan, James T. Thoresen.
United States Patent |
10,196,926 |
Ketchum , et al. |
February 5, 2019 |
Lubricating a rotating component during forward and/or reverse
rotation
Abstract
An assembly is provided for a turbine engine. This turbine
engine assembly includes a rotating component, a turbine engine
component and a lubrication system. The lubrication system is
adapted to lubricate the turbine engine component where the
rotating component rotates a first direction about an axis. The
lubrication system is also adapted to lubricate the turbine engine
component where the rotating component rotates a second direction
about the axis.
Inventors: |
Ketchum; David A. (Willington,
CT), Thoresen; James T. (Glastonbury, CT), James; Denman
H. (Windsor, CT), James; Reade W. (West Hartford,
CT), Sheridan; William G. (Southington, CT) |
Applicant: |
Name |
City |
State |
Country |
Type |
United Technologies Corporation |
Hartford |
CT |
US |
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Assignee: |
United Technologies Corporation
(Farmington, CT)
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Family
ID: |
54264700 |
Appl.
No.: |
14/683,824 |
Filed: |
April 10, 2015 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20150292359 A1 |
Oct 15, 2015 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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61978525 |
Apr 11, 2014 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01D
25/20 (20130101); F01D 21/00 (20130101); F02C
7/36 (20130101); F02C 7/06 (20130101); F05D
2260/40311 (20130101) |
Current International
Class: |
F01D
25/20 (20060101); F02C 7/06 (20060101); F01D
21/00 (20060101); F02C 7/36 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Kershteyn; Igor
Assistant Examiner: Fountain; Jason
Attorney, Agent or Firm: O'Shea Getz P.C.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to U.S. Provisional Patent
Application No. 61/978,525 filed Apr. 11, 2014, which is hereby
incorporated herein by reference in its entirety.
Claims
What is claimed is:
1. An assembly for a rotational system that includes a rotating
component, the assembly comprising: a bearing adapted to support
the rotating component; and a lubrication system adapted to
lubricate the bearing where the rotating component rotates a first
direction about an axis, and adapted to lubricate the bearing where
the rotating component rotates a second direction about the axis;
wherein the lubrication system comprises a first pump adapted to
direct lubricant to the bearing where the rotating component
rotates the first direction; and a second pump adapted to direct
lubricant to the bearing where the rotating component rotates the
second direction; wherein the first pump is adapted to direct
lubricant to the second pump where the rotating component rotates
the first direction.
2. The assembly of claim 1, wherein the second pump is adapted to
direct lubricant to the first pump where the rotating component
rotates the second direction.
3. The assembly of claim 1, wherein the lubrication system
comprises a first lubricant reservoir fluidly coupled with the
first pump; and a second lubrication reservoir fluidly coupled with
the second pump.
4. The assembly of claim 1, wherein the first pump is adapted to be
driven by torque from a shaft of the rotational system; and the
second pump is adapted to be driven by the torque from the shaft of
the rotational system.
5. The assembly of claim 1, wherein the bearing comprises a journal
bearing.
6. The assembly of claim 1, further comprising: a fan rotor; a
compressor rotor; and a gear train connected between the fan rotor
and the compressor rotor, the gear train including the bearing.
7. The assembly of claim 1, wherein the rotational system comprises
a turbine engine.
8. An assembly for a rotational system that includes a rotating
component, the assembly comprising: a bearing adapted to support
the rotating component; and a lubrication system adapted to
lubricate the bearing where the rotating component rotates a first
direction about an axis, and adapted to lubricate the bearing where
the rotating component rotates a second direction about the axis;
wherein the lubrication system comprises a first lubrication
circuit adapted to direct lubricant to the bearing where the
rotating component rotates the first direction; and a second
lubrication circuit adapted to direct lubricant to the bearing,
independent of the first lubricant circuit, where the rotating
component rotates the second direction.
9. The assembly of claim 8, wherein the first lubrication circuit
comprises a first pump; and the second lubrication circuit
comprises a second pump.
10. The assembly of claim 9, wherein the first lubrication circuit
is adapted to lubricate the first pump where the rotating component
rotates the first direction.
11. The assembly of claim 10, wherein the second lubricant circuit
is adapted to lubricate the second pump where the rotating
component rotates the second direction.
12. The assembly of claim 8, further comprising: a fan rotor; a
compressor rotor; and a gear train connected between the fan rotor
and the compressor rotor, the gear train including the bearing.
13. The assembly of claim 8, wherein the rotational system
comprises a turbine engine.
14. The assembly of claim 8, wherein the bearing comprises a
journal bearing.
15. A method involving a bearing and a rotating component of a
turbine engine, the method comprising: lubricating the bearing
where the rotating component rotates a reverse direction about an
axis; wherein the bearing supports the rotating component, and the
rotating component is operable to rotate a forward direction and
the reverse direction about the axis; and wherein the rotating
component rotates the reverse direction where a rotor of the
turbine engine is windmilling.
16. The method of claim 15, further comprising lubricating the
bearing where the rotating component rotates the forward direction
about the axis.
17. The method of claim 15, wherein the lubricating of the bearing
comprises directing lubricant to the bearing using a pump driven by
torque from a shaft of the turbine engine.
18. The method of claim 15, wherein the bearing comprises a journal
bearing.
Description
BACKGROUND OF THE INVENTION
1. Technical Field
This disclosure relates generally to lubricating a component of a
rotational system such as, for example, a turbine engine.
2. Background Information
A turbine engine typically includes a fan section, a compressor
section, a combustor section and a turbine section. Some turbine
engines may also each include a gear train, which rotationally
couples and transmits torque between a rotor of the turbine section
and a rotor of the fan section. Such a gear train may include a
plurality of gears and a plurality of journal bearings. The gears
are rotatably supported by the bearings, and rotationally couple
and transmit torque between the turbine rotor and the fan
rotor.
When the turbine engine is powered up, a lubrication system for the
turbine engine may lubricate the bearings of the gear train. For
example, a forward rotating engine shaft may mechanically drive a
pump to direct lubricant from a reservoir to the bearings. Such a
mechanically driven pump, however, cannot direct lubricant to the
bearings when the engine shaft is rotating in a reverse direction.
Rather, the reverse rotating engine shaft may drive the pump to
siphon air and/or lubricant from the bearings. Such reverse
rotation may occur, for example, where the turbine engine is
powered down and wind is blowing into a bypass gas path nozzle of
the turbine engine causing the fan rotor to windmill in the reverse
direction.
To prevent the unlubricated bearing of the gear train from seizing
during reverse rotation, the turbine engine may be configured with
a mechanical rotor lock. Such a rotor lock, however, may increase
cost and complexity of the turbine engine. In addition, if the
rotor lock is mistakenly left unengaged or fails, the unlubricated
bearings of the gear train may still be susceptible to seizing.
There is a need in the art for an improved lubrication system for a
turbine engine.
SUMMARY OF THE DISCLOSURE
According to an aspect of the invention, an assembly is provided
for a turbine engine. This turbine engine assembly includes a
rotating component, a turbine engine component and a lubrication
system. The lubrication system is adapted to lubricate the turbine
engine component where the rotating component rotates a first
direction about an axis. The lubrication system is also adapted to
lubricate the turbine engine component where the rotating component
rotates a second direction about the axis.
According to another aspect of the invention, an assembly is
provided for a rotational system that includes a rotating
component. This assembly includes a lubrication system and a
bearing adapted to support the rotating component. The lubrication
system is adapted to lubricate the bearing where the rotating
component rotates a first direction about an axis. The lubrication
system is also adapted to lubricate the bearing where the rotating
component rotates a second direction about the axis.
According to still another aspect of the invention, a method is
provided involving a bearing and a rotating component of a turbine
engine. The method includes a step of lubricating the bearing where
the rotating component rotates a reverse direction about an axis.
The bearing supports the rotating component. The rotating component
is operable to rotate a forward direction and the reverse direction
about the axis.
The first direction may be a forward direction. The second
direction may be a reverse direction. Alternatively, the first
direction may be a reverse direction. The second direction may be a
forward direction.
The turbine engine component may be configured as or otherwise
include a bearing adapted to support the rotating component. This
bearing may be configured as a journal bearing or any other type of
bearing.
The rotating component may be configured as or otherwise include a
gear or a shaft.
The assembly may include a fan rotor, a compressor rotor and a gear
train. The gear train may be connected between the fan rotor and
the compressor rotor. The gear train may include the rotating
component and the turbine engine component.
The lubrication system may include a first pump adapted to direct
lubricant to the turbine engine component where the rotating
component rotates the first direction. The lubrication may also or
alternatively include a second pump adapted to direct lubricant to
the turbine engine component where the rotating component rotates
the second direction.
The lubrication system may include a first pump adapted to direct
lubricant to the bearing where the rotating component rotates the
first direction. The lubrication system may also or alternatively
include a second pump adapted to direct lubricant to the bearing
where the rotating component rotates the second direction.
The first pump may be adapted to direct lubricant to the second
pump where the rotating component rotates the first direction. The
second pump may also or alternatively be adapted to direct
lubricant to the first pump where the rotating component rotates
the second direction.
The lubrication system may include a first lubricant reservoir
fluidly coupled with the first pump. The lubrication system may
also include a second lubrication reservoir fluidly coupled with
the second pump.
The first pump may be adapted to be driven by torque from a shaft
of the rotational system. The second pump may be adapted to be
driven by the torque from the shaft of the rotational system.
The lubrication system may include a first lubrication circuit
adapted to direct lubricant to the bearing where the rotating
component rotates the first direction. The lubrication system may
also or alternatively include a second lubrication circuit adapted
to direct lubricant to the bearing, independent of the first
lubricant circuit, where the rotating component rotates the second
direction.
The first lubrication circuit may include a first pump. In addition
or alternatively, the second lubrication circuit may include a
second pump.
The first lubrication circuit may be adapted to lubricate the first
pump where the rotating component rotates the first direction. The
second lubricant circuit may also or alternatively be adapted to
lubricate the second pump where the rotating component rotates the
second direction.
The bearing may be configured as or otherwise include a journal
bearing.
The bearing may rotate the reverse direction where a rotor of the
turbine engine is windmilling.
The method may include lubricating the bearing where the rotating
component rotates the forward direction about the axis.
The lubricating of the bearing may include directing lubricant to
the bearing using a pump driven by torque from a shaft of the
turbine engine.
The foregoing features and the operation of the invention will
become more apparent in light of the following description and the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side cutaway illustration of a turbine engine;
FIG. 2 is a cross-sectional illustration of a gear train for the
turbine engine of FIG. 1;
FIG. 3 is a block diagram of a lubrication system for the turbine
engine of FIG. 1;
FIG. 4 is a block diagram of the lubrication system of FIG. 3
during forward rotation operation; and
FIG. 5 is a block diagram of the lubrication system of FIG. 3
during reverse rotation operation.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a side cutaway illustration of a turbine engine 10. This
turbine engine 10 is configured as a geared turbofan engine and may
be included in an aircraft propulsion system.
The turbine engine 10 extends along an axial centerline 12 between
an upstream airflow inlet 14 and a downstream airflow exhaust 16.
The turbine engine 10 includes a fan section 18, a compressor
section 19, a combustor section 20 and a turbine section 21. The
compressor section 19 includes a low pressure compressor (LPC)
section 19A and a high pressure compressor (HPC) section 19B. The
turbine section 21 includes a high pressure turbine (HPT) section
21A and a low pressure turbine (LPT) section 21B. The engine
sections 18-21 are arranged sequentially along the centerline 12
within a housing 22, which includes a first engine case 24 and a
second engine case 26.
Each of the engine sections 18-19B, 21A and 21B includes a
respective rotor 28-32. Each of these rotors 28-32 includes a
plurality of rotor blades arranged circumferentially around and
connected to one or more respective rotor disks. The rotor blades,
for example, may be formed integral with or mechanically fastened,
welded, brazed, adhered and/or otherwise attached to the respective
rotor disk(s).
The fan rotor 28 is connected to a gear train 34, for example,
through a fan shaft 36. The gear train 34 and the LPC rotor 29 are
connected to and driven by the LPT rotor 32 through a low speed
shaft 37. The HPC rotor 30 is connected to and driven by the HPT
rotor 31 through a high speed shaft 38. The shafts 36-38 are
rotatably supported by a plurality of bearings 40; e.g., rolling
element and/or thrust bearings. Each of these bearings 40 is
connected to the second engine case 26 by at least one stationary
structure such as, for example, an annular support strut.
During operation, air enters the turbine engine 10 through the
airflow inlet 14, and is directed through the fan section 18 and
into a core gas path 42 and a bypass gas path 44. The air within
the core gas path 42 may be referred to as "core air". The air
within the bypass gas path 44 may be referred to as "bypass air".
The core air is directed through the engine sections 19-21 and
exits the turbine engine 10 through the airflow exhaust 16 to
provide forward engine thrust. Within the combustor section 20,
fuel is injected into a combustion chamber 46 and mixed with the
core air. This fuel-core air mixture is ignited to power the
turbine engine 10. The bypass air is directed through the bypass
gas path 44 and out of the turbine engine 10 through a bypass
nozzle 48 to provide additional forward engine thrust.
Alternatively, at least some of the bypass air may be directed out
of the turbine engine 10 through a thrust reverser to provide
reverse engine thrust.
FIG. 2 illustrates an exemplary embodiment of the gear train 34.
This gear train 34 includes a sun gear 50, a plurality of star
gears 51, a plurality of bearings 54 (e.g., journal bearings), and
a ring gear 52. The sun gear 50 is rotatable about the centerline
12. The sun gear 50 is connected to the low speed shaft 37, for
example, through a joint such as a spline joint. The star gears 51
are arranged circumferentially around the centerline 12 and
radially meshed between the sun gear 50 and the ring gear 52. Each
of the star gears 51 is rotatable about a respective axis. Each of
the star gears 51, for example, is rotatably connected to a
stationary gear carrier 56 through a respective one of the bearings
54. The gear carrier 56 may be connected to the second engine case
26 (see FIG. 1) through a support strut and/or a flexible support.
The ring gear 52 is rotatable about the centerline 12. The ring
gear 52 is connected to the fan shaft 36 (see FIG. 1), for example,
through a joint such as a bolted flange joint.
FIG. 3 illustrates a system 58 for lubricating at least one
component 60 of the turbine engine 10 of FIG. 1. The turbine engine
component 60 is described below and illustrated in FIG. 3 as one of
the bearings 54 (see FIG. 2) for ease of description. However, in
alternative embodiments, the lubrication system 58 may also or
alternatively lubricate at least one of the gears 50-52 (see FIG.
2), at least one of the bearings 40 (see FIG. 1), and/or any other
moving component(s) of the turbine engine 10.
The lubrication system 58 of FIG. 3 includes a primary lubrication
circuit 62, which lubricates the bearing 54 during forward
rotation. The lubrication system 58 also includes a secondary
lubrication circuit 64, which lubricates the bearing 54 during
reverse rotation independent of the primary lubrication circuit 62.
The term "forward rotation" may describe a (e.g., clockwise)
direction a respective rotating component rotates about an axis
when the turbine engine 10 is powered up. The term "reverse
rotation" may describe an opposite (e.g., counter-clockwise)
direction a respective rotating component rotates about an axis
when the turbine engine 10 is powered down; e.g., during
windmilling. An example of a rotating component is the star gear 51
that is rotatably supported by the respective bearing 54. Other
examples of rotating components include, but are not limited to,
the gears 50 and 52, the rotors 28-32, and the engine shafts
36-38.
The primary lubrication circuit 62 includes a forward rotation pump
66 and a primary lubricant reservoir 68 such as, for example, a
gutter, a sump or a tank. The forward rotation pump 66 may be
configured as a mechanically driven positive displacement pump. The
forward rotation pump 66 may be rotationally coupled to and driven
by torque from a rotating component of the turbine engine; e.g.,
the low speed shaft 31.
The forward rotation pump 66 is fluidly coupled inline between the
primary lubricant reservoir 68 and the bearing 54. For example, a
first inlet/outlet 70 (I/O) of the forward rotation pump 66 may be
fluidly coupled with an inlet/outlet 72 (I/O) of the primary
lubricant reservoir 68. A second inlet/outlet 74 (I/O) of the
forward rotation pump 66 may be fluidly coupled with at least one
first orifice 76 in the bearing 54.
The secondary lubrication circuit 64 includes a reverse rotation
pump 78 and a secondary lubricant reservoir 80 such as, for
example, a gutter, a sump or a tank. The reverse rotation pump 78
may be configured as a mechanically driven positive displacement
pump. The reverse rotation pump 78 may be rotationally coupled to
and driven by torque from a rotating component of the turbine
engine; e.g., the low speed shaft 31.
The reverse rotation pump 78 is fluidly coupled inline between the
secondary lubricant reservoir 80 and the bearing 54. For example, a
first inlet/outlet 82 (I/O) of the reverse rotation pump 78 may be
fluidly coupled with an inlet/outlet 84 (I/O) of the secondary
lubricant reservoir 80. A second inlet/outlet 86 (I/O) of the
reverse rotation pump 78 may be fluidly coupled with at least one
second orifice 88 in the bearing 54, which orifice 88 is discrete
from the first orifice 76. The second inlet/outlet 86 may also be
fluidly coupled with the second inlet/outlet 74 through, for
example, a conduit 90.
Referring to FIG. 4, during forward rotation operation, the forward
rotation pump 66 directs lubricant (e.g., oil) from the primary
lubricant reservoir 68 to the first orifice 76 thereby lubricating
the bearing 54. This lubricant may subsequently be provided to the
meshing surfaces of the gears 50-52 (see FIG. 2) thereby
lubricating the gears 50-52. The forward rotation pump 66 may also
direct the lubricant to the second inlet/outlet 86 thereby
lubricating the reverse rotation pump 78. The reverse rotation pump
78 (if engaged and operational), in contrast, may siphon air (and
sometimes a small quantity of lubricant) from the second orifice 88
and direct this air into the secondary lubricant reservoir 80. This
suction may also aid in directing the lubricant through the conduit
90 from the forward rotation pump 66.
Referring to FIG. 5, during reverse rotation operation, the reverse
rotation pump 78 directs lubricant (e.g., oil) from the secondary
lubricant reservoir 80 to the second orifice 88 thereby lubricating
the bearing 54. This lubricant may subsequently be provided to the
meshing surfaces of the gears 50-52 (see FIG. 2) thereby
lubricating the gears 50-52. The reverse rotation pump 78 may also
direct the lubricant to the second inlet/outlet 74 thereby
lubricating the forward rotation pump 66. The forward rotation pump
66 (if engaged and operational), in contrast, may siphon air (and
sometimes a small quantity of lubricant) from the first orifice 76
and direct this air into the primary lubricant reservoir 68. This
suction may also aid in directing the lubricant through the conduit
90 from the reverse rotation pump 78.
As described above in the background section, a prior art turbine
engine may include a mechanical rotor locking device to prevent
rotation of its rotors since its components are not lubricated
during reverse rotation. The lubrication system 58 of FIG. 5, in
contrast, can accommodate reverse rotation operation with its
secondary lubrication circuit 64. The secondary lubrication circuit
64 therefore may provide a failsafe feature that prevents or
reduces engine damage if its rotor locking device fails. The
secondary lubrication circuit 64 may also enable the turbine engine
10 to be configured without a rotor locking device.
The lubrication system 58 may have various configurations other
than that described above and illustrated in the drawings. For
example, the forward rotation pump 66 may be configured with a
higher pump flow rate than the reverse rotation pump 78. The
primary lubricant reservoir 68 may be configured with a higher
lubricant holding capacity than the secondary lubricant reservoir
80. The primary lubricant reservoir 68 and the secondary lubricant
reservoir 80 may be fluidly coupled together, for example, by a
conduit. One of the lubricant reservoirs 68 and 80 may be omitted
and both pumps 66 and 78 may be fluidly coupled to a common
lubricant reservoir (e.g., the remaining reservoir). The conduit 90
may be omitted where, for example, the pumps 66 and 78 are
lubricated by another lubrication system or sub-system of the
lubrication system 58. The present invention therefore is not
limited to any particular lubrication system configurations.
The lubrication system 58 may be included in various turbine
engines other than the one described above as well as in other
types of rotational systems. The lubrication system 58, for
example, may be included in a geared turbine engine where a gear
train connects one or more shafts to one or more rotors in a fan
section, a compressor section and/or any other engine section.
Alternatively, the lubrication system 58 may be included in a
turbine engine configured without a gear train. The lubrication
system 58 may be included in a geared or non-geared turbine engine
configured with a single spool, with two spools (e.g., see FIG. 1),
or with more than two spools. The turbine engine may be configured
as a turbofan engine, a turbojet engine, a propfan engine, or any
other type of turbine engine. The present invention therefore is
not limited to any particular types or configurations of turbine
engines or rotational systems.
While various embodiments of the present invention have been
disclosed, it will be apparent to those of ordinary skill in the
art that many more embodiments and implementations are possible
within the scope of the invention. For example, the present
invention as described herein includes several aspects and
embodiments that include particular features. Although these
features may be described individually, it is within the scope of
the present invention that some or all of these features may be
combined within any one of the aspects and remain within the scope
of the invention. Accordingly, the present invention is not to be
restricted except in light of the attached claims and their
equivalents.
* * * * *